Short for "rolling papers", thin sheets used to roll joints, generally of marijuana.

"I'm broke as fuck and I don't get paid til the first of next month.
But if you care to join me, I was about to roll this next blunt.
But I don't got no weed, no Phillies, or no papers.
Plus I'm a rapist and a repeated prison escapist..."
-Eminem ("As The World Turns")